The invention relates to snap fasteners in general, and more particularly to improvements in snap fasteners of the type wherein a male component having a male coupling element and a first rivet is repeatedly connectable to and disengageable from a female component having a female coupling element and a second rivet, wherein the first rivet serves to preferably permanently secure the male coupling element to a first carrier (such as a first piece of fabric) and wherein the second rivet serves to preferably permanently secure the female coupling element to a second carrier (such as a second piece of fabric).
Snap fasteners of the above outlined character are often utilized on garments, particularly in lieu of or in addition to customary buttons. If a snap fastener is to separably connect two overlapping pieces of fabric in a garment, the male coupling element is normally located at the outer side of the inner (overlapped) piece of fabric and is held in such position by the first rivet which extends through the inner piece of fabric. The female coupling element is located at the inner side of the outer (overlapping) piece of fabric and is held in such position by the second rivet which extends through the outer piece of fabric. This ensures that the so-called head of the male coupling element can be introduced into and releasably held in the complementary socket of the female coupling element. The rivets have shanks or shafts which extend through the respective pieces of fabric and are deformed in the respective coupling elements to establish a reliable (normally permanent) connection between the pieces of fabric and the associated coupling elements. The flange or base of the second rivet is exposed at the outer side of the outer piece of fabric, and the male coupling element is exposed at the outer side of the inner piece of fabric.
In the absence of a reliable seal between the flange of the second rivet and the outer fabric layer, wind and/or rain can penetrate through the outer piece of fabric where the shank of the second rivet extends through the outer piece of fabric. Analogously, wind and/or rain can penetrate through the inner piece of fabric in the region where the shank of the first rivet extends through the second piece of fabric. Reliable seals at locations where the shanks of the rivets extend through the respective pieces of fabric are particularly desirable when a snap fastener is used on a garment (such as a windbreaker jacket, a raincoat, a slicker, a jacket to be worn by a skier and many other types of outdoor garments and garments to be worn by sports persons) which is likely to be exposed to elements when in actual use. Many garments of the just outlined character embody so-called climatic membranes which overlie pieces of textile material and are impermeable to fluids. The outer layer (namely the membrane) of such twin-layer structure should prevent the penetration of wind and/or moisture but the inner layer should be free to "breathe".
It has been found hat the ability of the twin-layer structure to prevent penetration of wind and/or moisture is often destroyed at locations where the shanks of the rivets penetrate through the impermeable membranes. Attempts to seal the perforated portions of the membranes include the utilization of strips which are bonded (e.g., welded or adhesively secured) to the perforated portions of the membranes, normally at the inner sides of the respective pieces of fabric. The application of sealing strips is a time-consuming operation which contributes to the cost of the ultimate product, and the applied sealing strips detract from the appearance of the finished garment.